IQ. What we found out this week.

Sure, but can Elvis do algebra?

To Elvis the Welsh corgi, it was probably just a massive game of fetch with his favorite tennis ball. But his owner was using him, on an outing to Lake Michigan, to solve a calculus problem.

"Most calculus students are familiar with the problem of finding the optimal path from Point A to Point B," said Tim Pennings, associate professor of mathematics at Hope College in Holland, Mich. "Standing on the water's edge at Point A, I throw the ball into the water at Point B. Elvis runs along the shore a portion of the way, then plunges into the lake at a point of his choosing and swims diagonally to the ball. By the look in Elvis' eyes, it seems clear that his objective is to retrieve it as quickly as possible."

Pennings decided to test his shortest-distance theory. He clocked his dog's running and swimming speeds and measured where the ball was thrown, where it landed and where Elvis hit the water. Plotting the results revealed that, in most cases, Elvis chose almost the same path as the optimal path calculated mathematically.

"Though he does not do the calculations, Elvis' behavior is an example of the uncanny way in which nature often finds optimal solutions," Pennings said.

His findings appear in this month's issue of The College Mathematics Journal.